The 3rd Generation Partnership Project (3GPP) is a globally applicable third generation mobile phone system specification that is a result of collaboration between various groups of telecommunications associations, including the European Telecommunications Standards to Institute, the Association of Radio Industries and Businesses/Telecommunication Technology Committee (ARIB/TTC), China Communications Standards Association, and the Alliance for Telecommunications Industry Solutions. 3GPP release 99 specified the first Universal Mobile Telecommunications System (UMTS) 3G network that incorporates a Code Division Multiple Access (CDMA) air interface.
In 3GPP, release 99, control channel information is carried over a Dedicated Physical Control Channel (DPCCH) and user data is carried over a Dedicated Physical Data Channel (DPDCH). Inner Loop Power Control (ILPC) in 3GPP release 99 aims to maintain a DPCCH signal-to-interference ratio (SIR) level associated with a user device's uplink transmissions around a DPCCH SIR target. The DPCCH SIR target is regularly updated by an Outer Loop ower Control (OLPC) scheme. OLPC aims at maintaining a predetermined block error rate (BLER) by updating the DPCCH SIR target based on the transport block error statistics.
In the evolved 3G standards, High Speed Uplink Packet Access (HSUPA), also called “Enhanced Uplink” (EUL), has been introduced. The aim of EUL is to increase the uplink data transfer speed in the UMTS environment and it offers data speeds of up to 5.8 Mbps on the uplink. EUL achieves this high performance based, in part, on the use of time division multiplexing (TDM), in addition to CDMA, to create multiple, repeating transmission time intervals (TTIs) on the uplink that can be allocated to user equipment that is attempting to transmit at high speed on the uplink.
In EUL, the DPCCH is still used as a control channel. Additionally, two new physical uplink data channels have been introduced for EUL: an Enhanced Dedicated Physical Data Channel (E-DPDCH) and an Enhanced Dedicated Physical Control Channel (E-DPCCH). The DPCCH carries control channel information such as pilot symbols for channel estimation, etc. The E-DPCCH is used to carry other control data, such as an Enhanced Transport Format Combination Index (E-TFCI), Hybrid Automatic Repeat Request (HARQ) profile, etc. EUL also includes ILPC and OLPC techniques used in 3GPP release 99. Similar to 3GPP release 99, the ILPC for EUL also aims at maintaining a DPCCH SIR level around a DPCCH SIR target. The OLPC for EUL updates the DPCCH SIR target by monitoring the number of transmission attempts, instead of maintenance of a predetermined BLER as occurs in 3GPP release 99.